I actually specifically made a trip to Milwaukee 1/3 for the Harley museum and 2/3 for ASS (that acronym was definitely deliberate). I've enjoyed my visits to ax-man surplus [0] in Minneapolis enough that when I heard about a similar store it was enough to justify a 500mi weekend bike trip. The stores are very similar, but anyone lucky to live near their store knows that the inventory changes enough that each visit is a unique experience and you won't see the same things twice.

saveitforparts on YouTube did an excellent tour/example video of ax-man [1] which gives a good idea of the type of store ASS is and the vibe. Even if you aren't local to the upper Midwest, I'd highly recommend donating to keep this store alive. It very much fits with the old-school hacker ethos, and keeping spaces like this alive helps preserve that culture and exposes younger people to the idea of DIY/punk/hacker and the ability to repurpose old/interesting stuff.

Side note, I'm surprised that these types of scientific surplus stores have lasted longer in the upper Midwest than places like silicon valley or near bell labs in NJ. They aren't open for retail anymore and didn't have the same sense of humor, but Surplus Sales of Nebraska [2] is also an excellent example from this area of the country. I hadn't ordered since last year, they had held on to a delightful web 1.0 site up until sometime in the last year and are a legit supplier for really oddball stuff.

[0] https://www.ax-man.com/pages/the-nature-of-surplus

[1] https://www.youtube.com/watch?v=U-uJPIhAUu4

[2] https://www.surplussales.com/